Scaffolding clamp



y 1950 A. H. HAWES 2,506,640

SCAFFOLDING CLAMP Filed Nov. 27, 1946 2 Sheets-Sheet 1 ATTORNEY,

y 1950 A./H. HAWES 2,506,640

SCAFFOLDING CLAMP Filed NOV. 27, 1946 2 Sheets-Sheet 2 INVENTOR ATTORNEY Patented May 9, 1950 'PA'EENT OFFICE asig'nor, l yimesne eassignments, to Kwikform 4.Limited,.-Small Heath, Birmingham, Eng-land,

.aTBrit'ish company l nmili'cationfNovember 27, '1'946, Serial N 0.1712382 'JFImGratF-Britain December 19, 1945 In' :assembling :such a structure fromsscaffolding 'Ofslihfi above vhind iteis atspresent usual. to erect at isuitable-iintervals tWQeBOWSWOf vertical columns, adjacentmeIumns-imthe two :rows being connected togethervviby transverse, v-putlog tubes :pair of *coiumnseso Jormed ibeing .1 also connected to the meat i-pair ror lpairs byhorizontal ledger Ttubies, which-again are heldiin place .ibyiseparate :clamps. :Astaging-or working platiorm, consisting of a plurality of gparallel wooden battens, 415 then 'laid upon the lputlogstubes Ito form the platform or staging.

With such an arrangement, xunless the transverse putlog tubeseare yeryrcarefully located during assembly ,of ithewseafiolding, the battens .laid thereon .wiillmnot proi'zide aflevl platformiand it fimay beonecessaryto.oyerlap'ithe ends-of adjacent battens, oriadjacentsections of the-staging, with :the result .that dangerous steps 'fliable to trip-a worlsmanraraproduced.

'-With \a view itolovercomingv this ldifliculty, I .have .in my yprior RatentNo. J2,47.2,423 .described vandclain'led .foruse .in the erection of :scafiold- .ing .of the above kind, a.scaiold.irame unit comprising two vertical tubularmembersrigidly/and 37$} .permanently connected together a :horizontal mexnber which .is :adapted ito engage. and .sup- -vport a substantially.ihorizontalistaging or. plat- :form extending transversely of the vframe unit, and :a pair of' clamping devicesisecured mermanentl-y to :the :frame .unitlwwh ichare adapted .for clamping engagement with tubular iscaiiolding elements iorming ledger e'lementsrand extend- ..ing transversely of athes-framesunit to secure the unit-to a second. similar Jftame iunitior other-struc- --.ture, said clamping devicesi being disposed one ad-j acentato each unction between ithe-zsaid :horizontal (and vertical members LOT the drama unit, .so that they are adapted to support :the transverse rledgereelements .in a position relative to-the horizontal membenof reach unit,fo1' carrying put-- Jog elements narallel toithe horizontal member sand at hesameL-levehto,providers, levelesunport 'lf'or :a, platform-slur stag- 38.

. flhe abject of tbspreeentdnrention :1 :to

7 1 2 vide a new-or improvedscaffoldingclamp -ior;se curing the putlog elements to the ledger elements vinscailiolding of "the kind specified rand WhiChiiS particularly applicable to :the scafiolding vforming thesubject of my prior patentaforesaid.

Referring :to .the drawings:

:Figure ltis aepersnective .view of one form of scaffolding structure incorporating scaffolding clamps in accordance with this invention.

[Figure 2 an enlarged cross sectional v-iew of the upper part of the structureshown Figure .1 and depicting one .ofH-the -=scaffold ing clamps aforesaid.

.Figure 3 a perspective -vieW of the-scaffolding clamp shown in Figure .2.

[Figure 4 is a cross sectional sideielevation of the clamp shown in Figure 3, and

"Figure 5 isan .endelevationoffthe same clamp.

In Figure 1 there is depicted the vscaffolding structure described-in my prior .patent aforesaid which comprises lscaliold frame units indicated generally at 20, each unit including two vertical tubular members =2 I 22 rigidly and permanently connected together by .a horizontal member -2.3, which in the construction illustrated is also formed as .a tube, which horizontal :member is adapted toengage and supporta-lsubstantially horizontal staging .01 platform which extends transversely ,of the frame unit, which platform or .stagingin the arrangement.illustrateduis iconstituted by a,plurality of Wooden battens 1'24.

Each frame unitcfurther comprises a pair or clamping devices 25 disposed adjacent to the vjunction of the horizontaimember 2Z3 with-each of the-two vertical members 21, 22 .as described in .my zprior specification and. the clamping devices'25 are adapted to receive andiengagetransverse'ly extending tubular ledgerelements 19 v In utilizingnsuchirame unitscfor the supportling-of arsuhstantiallyihorizontal platformor stag- .ing ionuse, for example, in-the construction of a wall, a numberof similar -units would be taken and disposed in transversely and l horizontally spaced relationship-ms .shovvnrin the lower of Figure 1, the units being connected v-rigidly together by placing vtheir-i011zonral- .-transversely with the ,ba ttensof the same diameter as the ledger elements are indicated at 43 extending parallel to and intermediate the horizontal members 23 with their upper surfaces level with the upper surfaces of the members 23 as shown in Figure 2. The length of the putlog elements is the same as or slightly greater than the length of the horizontal members 23, and the putlog elements are secured to the ledger elements by putlog clamps 41 which form the subject of the present invention.

The putlog clamps 47 for securing the putlo elements 46 to the ledger elements 29 are shown more particularly in Figures 3 to 5 of the drawings and comprise each a body of substantially U shape including a pair of parallel limbs F spaced apart by a distancesufiicient to receive therebetween the ledger element 29 the limbs at their free ends being forked to provide in each end an opening 18 to receive the putlog element 46, the outer end of each opening having a width less than the diameter of the putlog element and the sides of each opening 18 being curved so that the opening is of somewhat oval shape and the ends 18 of the forks engage with the putlog element and prevent it passing vertically upwardly through the opening. Thus, the limbs 11 comprise a main body portion and two bowed integral arms. 7

The maximum'width of the opening is made somewhat greater than the external diameter of the putlog element.

The two limbs 16 are joined by a connecting part 8!] provided centrally with a threaded opening 8| in which works a clamping screw 82, the head 83 of which is flattened and provided with an opening 84 to receive a tommy-bar, while the inner end of the screw is connected rotatably to a pressure plate 85, the inner face of which is of part-circular form as shown in Figure 5 and shaped to engage with the adjacent ledger element 29, the pressure plate being secured permanently to the clamping screw 82 by making the inner end of the latter of reduced section as indicated at 8B, the reduced end passing through a hole in the pressure plate and being riveted over within a recessed portion 81 on the inner face of the plate, so that the inner end of the screw is out of contact with the ledger element 29.

It is preferred to separate the limbs TI, 11 by a distance appreciably greater than the diameter of a, ledger tube 29, as best shown in Fig. 5. Thus, the 'clamp may be turned with respect to the ledger tube to facilitate application of the putlog tube thereto.

By tightening up the screw 82 the ledger ele ment 29 is forced against the putlog element 46 which is thereby pressed against the ends I9 of the clamp limbs and the two elements 29, 46 are frictionally located against relative movement.

In order to provide a flush surface for the battens where they pass over the putlog clamp above described the free ends of the limbs T? are flattened as indicated at 88 on their upper sides so that they do not project above the putlog element 46. As best seen in Fig. 4, the outer ends of the arms are separated by a distance less than the outside diameter of a putlog tube and terminate in a common plane which is substantially tangential to the external surface of the putlog tube 46 when positioned between the arms and against their ends. a

As a result a substantially flush surface is presented to the under-side of the battens 24 free from projections so the battens are substantially horizontal and present, if of the same thickness, at substantially flush upper surface thereby avoid ing dangerous steps or projections liable to trip a workman on the platform or staging.

In the construction actually illustrated in Figures 3 to 5 the limbs 11 of the clamp are formed separately from the connecting part thereof and are secured thereto by providing the connecting part at opposite sides with a pair of lugs 89 which extend through correspondingly disposed openings in the'limbs H the free ends of the lugs being riveted over to secure the limbs to the connecting part 80. Alternatively the limbs 11 may be welded to the connecting part 80.

With either arrangement, the connecting part 80 can be made of a thickness greater than that necessary for the thickness of the limbs I1 so that the connecting part is of a substantial strength and provides a threaded opening 8| of depth suflicient to provide adequate thread support for the clamping screw 82 and ensures that it is mounted in firm clamping engagement with the ledger element 29 when the screw is tightened.

Such an arrangement would be more diiiicult to achieve if the connecting part 80 were made integral with the limbs 11 and it would probably be necessary to provide the connecting part 80 with a separate nut welded or otherwise secured thereto for engaging with the clamping screw so as to provide a sufiicient depth ofscrew-thread to engage with the screw.

What I claim then is: V

1. For use in clamping toa ledger tube a putlog tube disposed immediately above and transversely to the ledger tube, a substantially U-shaped clamp comprising: a connecting part; a pair of substantially parallel coextending limbs, each joined at one end thereof to said connecting part, said limbs being separated by said connecting part at a distance appreciably greater than the diameter of a ledger tube; the ends of said limbs remote from said connecting part being forked at equal distances from said connecting part to provide on each limb two arms separated by an elliptical opening the major axis of which extends in the direction of the length of the limb, and the minor axis of which is greater than the outside diameter of a putlog tube; and a clamping screw carried by said connecting part and extending therefrom into the opening between said limbs; whereby application of clamping pressure by said clamping'screw to aledger tube disposed between said pair of limbs clamps the ledger tube to a putlog tube extending through the elliptical openings in said limbs and wedges said putlog tube firmly between the arms of each of said limbs.

2 For use in clamping to ai-le'dger tube a put- .log tube'disposed immediately above and transversely to the ledger tube, a substantially U- shaped clamp comprising: a connecting part; a pair of substantially parallel coextending limbs, each joined'at one end thereof to said connecting part, said limbs-being separatedby 'said connectingpart at a distance appreciably greater than the diameter of a ledger tube; the ends of said limbs remote from said connecting part being forked at equal distances from said connecting part to provide on each limb two arms separated by an elliptical opening the major axis of which extends in the direction of the length of the limb, and the minor axis of which is greater than the outside diameter of a putlog tube, the outer ends being separated by a distance less than the diameter of a putlog tube; and a clamping screw carried by said connecting part and extending therefrom into the opening between said limbs; whereby application of a clamping pressure by said clamping screw to a ledger tube disposed between said pair of limbs i,

clamps the ledger tube to a putlog tube extending through the elliptical openings in said limbs and wedges said putlog tube firmly between the arms of each of said limbs.

3. For use in clamping to a ledger tube a putlog tube disposed immediately above and transversely to the ledger tube, a substantially U- shaped clamp comprising: a connecting part; a pair of substantially parallel coextending limbs,

each joined at one end thereof to said connecting part, said limbs being separated by said connecting part at a distance appreciably greater than the diameter of a ledger tube; each of said limbs comprising: a main body portion, and two integral arms extending away from the end of said limb which is joined to said connecting part, said arms being bowed to define therebetween an elliptical opening the major axis of which extends in the direction of the length of said arms and the minor axis of which is greater than the outside diameter of a putlog tube, the outer ends of said arms being separated by a distance less than the outside diameter of a putlog tube; and a clamping screw carried by said connecting part and extending therefrom into the space between said limbs; whereby application of clamping pressure by said clamping screw to a ledger tube disposed between said pair of limbs clamps the ledger tube to a putlog tube extending through the elliptical openings a,

in said limbs and wedges said putlog tube firmly between the arms of each of said limbs.

4. For use in clamping to a ledger tube a putlog tube disposed immediately above and transversely to the ledger tube, a substantially U- shaped clamp comprising: a connecting part; a pair of substantially parallel coextending limbs, each joined at one end thereof to said connecting part, said limbs being separated by said connecting part at a distance appreciably greater than the diameter of a ledger tube; each of said limbs comprising: a main body portion, and two integral arms extending away from the end of said limb which is joined to said connecting part, said arms being bowed to define therebetween an elliptical opening the major axis of which extends in the direction of the length of said arms and the minor axis of which is greater than the outside diameter of a putlog tube, the outer ends of said arms being separated by a distance less than the outside diameter of a putlog tube, the arms of both limbs terminating in a common plane substantially tangential to the external surface of a putlog tube positioned between said bowed arms of both limbs and pressed against the open ends thereof; and a clamping screw carried by said connecting part and extending therefrom into the space between said limbs; whereby application of clamping pressure by said clamping screw to a ledger tube disposed between said pair of limbs clamps the ledger tube to a putlog tube extending through the elliptical openings in said limbs and wedges said putlog tube firmly between the arms of each of said limbs.

ALBERT HENRY HAWES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,044,700 Jones June 16, 1936 2,476,863 Hawes July 19, 1947 FOREIGN PATENTS Number Country Date 322,560 Great Britain Dec. 12, 1929 423,151 Great Britain Jan. 25, 1935 

